<%#
 Copyright 2013-2020 the original author or authors from the JHipster project.

 This file is part of the JHipster project, see https://www.jhipster.tech/
 for more information.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
-%>
#!/usr/bin/env bash

KEYSPACE_NAME=<%= baseName.toLowerCase() %>

unset scripts
declare -A scripts

function log {
    echo "[$(date)]: $*"
}

function logDebug {
    ((DEBUG_LOG)) && echo "[DEBUG][$(date)]: $*"
}

function exitWithError() {
    echo "ERROR :
        $*"
    exit 1
}

#usage checks
if [ -z "$1" ]; then
    echo "usage: ./execute-cql cqlFile.cql"
    exit 1
fi
if [ -z "$CASSANDRA_CONTACT_POINT" ]; then
    echo "CASSANDRA_CONTACT_POINT environment variable must be defined"
    exit 1
fi

cqlFile=$1
filename=$(basename "$1")

#load already executed scripts in the `scripts` global variable: dictionary[scriptName->checksum]
function loadExecutedScripts {
    #allow spaces in cqlsh output
    IFS=$'\n'
    local rows=($(cqlsh -k $KEYSPACE_NAME -e "select * from schema_version" $CASSANDRA_CONTACT_POINT | tail -n+4 | sed '$d' |sed '$d'))

    for r in "${rows[@]}"
    do
        local scriptName=$(echo "$r" |cut -d '|' -f 1 | sed s'/^[[:space:]]*//' | sed s'/[[:space:]]*$//')
        local checksum=$(echo "$r" |cut -d '|' -f 2 | sed s'/^[[:space:]]*//' | sed s'/[[:space:]]*$//')
        scripts+=(["$scriptName"]="$checksum")
    done
    unset IFS
}

function exists {
  if [ "$2" != in ]; then
    echo "Incorrect usage."
    echo "Correct usage: exists {key} in {array}"
    return 1
  fi

  eval '[ ${'$3'[$1]+exists} ]'
}

function checksumEquals {
    local checksum=$(md5sum $cqlFile | cut -d ' ' -f 1)
    local foundChecksum=${scripts[${filename}]}

    if [[ "$checksum" == "$foundChecksum" ]]; then
        logDebug "checksum equals for $cqlFile, checksum=$checksum"
        return 0
    else
        logDebug "different checksum found for $cqlFile
        checksum=$checksum
   foundChecksum=$foundChecksum"
        return 1
    fi
}

function isExecuted {
    if exists $filename in scripts; then
        if checksumEquals $cqlFile; then
            return 0
        else
            exitWithError "$cqlFile has already been executed but has a different checksum logged in the schema_version table.
            scripts must not be changed after being executed.
            to resolve this issue you can:
            - revert the modified script to its initial state and create a new script
            OR
            - delete the script entry from the schema_version table
            "
        fi
    else
        return 1
    fi
}

function executeCqlScript {
    log "execute: $cqlFile"
    cqlsh -k $KEYSPACE_NAME -f $cqlFile $CASSANDRA_CONTACT_POINT

    # if execution failed
    if [ $? -ne 0 ]; then
        exitWithError "fail to apply script $filename
        stop applying database changes"
    fi
    logDebug "execution of $cqlFile succeeded"
}

function logExecutedScript {
    local duration=$1
    local checksum=$(md5sum $cqlFile | cut -d ' ' -f 1)

    logDebug "save $cqlFile execution in schema_version table"
    local query="INSERT INTO schema_version (script_name, checksum, executed_by, executed_on, execution_time, status) VALUES ('$filename', '$checksum', '$USER', toTimestamp(now()), $duration, 'success');"
    cqlsh -k $KEYSPACE_NAME -e "$query" $CASSANDRA_CONTACT_POINT
}

loadExecutedScripts
if isExecuted; then
    logDebug "skipping $cqlFile already executed"
else
    _start=$(date +"%s")
    executeCqlScript
    _end=$(date +"%s")
    duration=`expr $_end - $_start`
    logExecutedScript $duration
    log "$cqlFile executed with success in $duration seconds"
fi
